Ocular fundus imaging is used to examine and record images of internal structures in the back the eye (the ocular fundus), including structures such as the retina, optic disc, macula, and posterior pole. Fundus imaging can be used to detect and monitor diseases that affect the eye. Conventional table-top fundus imaging devices are impractical for some patients, such as infants, young children, and bedridden patients who cannot hold still or maneuver into the necessary position for proper eye alignment with the camera. Many portable hand-held fundus cameras are very expensive and are difficult or awkward to use. A hand-held camera can be used in an indirect ophthalmoscope arrangement but still needs a condensing lens held in the other hand. This occupies both hands of the examiner, with manipulation of the lids or scleral depression by the second hand no longer being possible. In addition, most ophthalmologists are not accustomed to such a bi-manual camera aiming technique. A head-mounted indirect ophthalmoscope with an integrated camera is ideal, but existing such devices have flaws that affect image quality. For instance, one such existing head-mounted indirect ophthalmoscope with an integrated camera places the effective camera aperture between the effective apertures of the examiner's two pupils. Consequently, this indirect ophthalmoscope with an integrated camera can allow the examiner to obtain a good monocular view, but the instrument can be easily misaligned for the camera, causing vignetting and poor quality images. Also, stereoscopic imaging of the ocular fundus is not possible with existing head-mounted indirect ophthalmoscopes.
Accordingly, there is a need in the art for a fundus imaging device, using manipulation that is familiar to, and easily used by the ophthalmologist that provides reliable, quality images.